/*******************************************************************************
 * Copyright  2015 rzorzorzo@users.sf.net
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package org.rzo.netty.ahessian.rpc.server;

import java.util.Date;
import java.util.HashMap;
import java.util.Map;

import org.rzo.netty.ahessian.Constants;
import org.rzo.netty.ahessian.rpc.message.HessianRPCCallMessage;
import org.rzo.netty.ahessian.rpc.message.HessianRPCReplyMessage;
import org.rzo.netty.ahessian.session.Session;

/**
 * Default implementation of a {@link Continuation}.
 */
class DefaultContinuation implements Continuation, Constants
{

	/** The service. */
	private ContinuationService _service;

	/** The call request message. */
	private HessianRPCCallMessage _message;

	/** The headers for reply message. */
	private Map _headers;

	/** Indicates if the continuation has been completed. */
	private boolean _completed = false;

	/** Time to live. */
	private Date _ttl;

	private Session _session = null;

	/**
	 * Instantiates a new default continuation.
	 * 
	 * @param message
	 *            the message
	 * @param service
	 *            the service
	 */
	DefaultContinuation(HessianRPCCallMessage message,
			ContinuationService service, Session session)
	{
		_service = service;
		_message = message;
		_headers = _message.getHeaders();
		if (_headers == null)
			_headers = new HashMap();
		Long ttl = (Long) _headers.get("TTL");
		if (ttl == null)
			_ttl = new Date(Long.MAX_VALUE);
		else
			_ttl = new Date(System.currentTimeMillis() + ttl.longValue());
		_headers.put(COMPLETED_HEADER_KEY, Boolean.FALSE);
		_session = session;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.rzo.netty.ahessian.rpc.server.Continuation#complete(java.lang.Object)
	 */

	public void complete(Object result)
	{
		checkCompleted();
		_completed = true;
		sendReply(result, null);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.rzo.netty.ahessian.rpc.server.Continuation#fault(java.lang.Throwable)
	 */

	public void fault(Throwable result)
	{
		checkCompleted();
		_completed = true;
		sendReply(null, result);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.rzo.netty.ahessian.rpc.server.Continuation#getTTL()
	 */

	public Date getTTL()
	{
		return _ttl;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.rzo.netty.ahessian.rpc.server.Continuation#send(java.lang.Object)
	 */

	public void send(Object result)
	{
		checkCompleted();
		sendReply(result, null);

	}

	private void checkCompleted()
	{
		if (_completed)
			throw new RuntimeException("Continuation already completed");
		if (System.currentTimeMillis() > _ttl.getTime())
		{
			_completed = true;
			throw new RuntimeException("Continuation already completed");
		}
	}

	private void sendReply(Object result, Object fault)
	{
		if (_completed)
			_headers.put(COMPLETED_HEADER_KEY, Boolean.TRUE);
		// TODO set reply headers
		_service.writeResult(new HessianRPCReplyMessage(result, fault, _message));
	}

	public Session getSession()
	{
		return _session;
	}

}
